Drusilla did it! Yep. That's my theory. I figure that the soul doesn't leave the body until perhaps the third or second last breath. This is why vampires generally wait until right before death until turning their victims. Drusilla turned William wrong, while his soul is still in his body. Deliberately. Why? As a 'gift,' to Angelus. She figures Angelus would find it 'fun,' to destroy ole William's soul the 'old fashioned,' read, 'human,' way. IE: through torture, abuse, brainwashing, gaslighting, etc.
This accounts for why William didn't seem any different really after he was turned and why he turns his mom with the intention of healing her, etc. Angelus realises 'somethings up,' in that episode, is it 'destiny,' that William walks in on Angelus and Dru? Anyways, he confronts Drusilla, she confesses, he's happy and they agree to pull a kind of 'good cop/bad cop,' routine with Dru as 'good cop,' to Angelus' 'bad.' And why didn't they just destroy his soul completely? The curse silly! Yep. I figure that if it hadn't been for the curse, Spike would have turned out to be a thousand times worst then Angelus, but...the curse saved him! Angelus never got to finish the job.
I see his soul as being in a 'vegetative coma state,' so to speak. You know the kind, a coma where everyone says, 'pull the plug, he's gone,' but technically still alive. The soul still being there, accounts for his ability to love and to 'care/caretake.' (Personally, I find his ability to caretake, to be caring actually more profound then his ability to love. ) But sinces the soul is basically in a coma, it doesn't have the strength/capability to influence Spike in any greater way. That electrical chip they place into his brain perhaps kickstarts some new electron pathways, slowly inducing the soul out of 'coma state.' The mind wipe as well as being completely isolated from other vampires, Drusilla and Angelus wipes out just enough of his 'Spike,' identity to allow the soul to begin to heal.
The ritual that he went through to 'win back his soul,' is just that. A ritual. The demon didn't actually 'give the soul back,' but 'healed it to a place where it's functioning properly again.'
So that's been my main theory since he got his soul back. Lately, in the last couple of weeks, however, I've begun to have a slight variation on this theroy.
Basically the how and why are the same. He is basically William after he's turned, no different, just stronger with fangy teeth and better eyesight! LOL When he turns his mother he does it out of good intentions. To cure her. It's only when his mom turns on him, that he understands what HE is and what he's made HER into. That's the trauma. Not so much the 'you've got the hots for me comments,' but the realization of what he is, what he's done to her, and killing her TWICE not just once. After that, he's pretty much lost every bit of identity he had. Talk about 'one bad day.'
So you've got: creative rejection and loss of creative identity, social rejection, rejection of love, rejection of him being a 'good man,' which isn't good enough for the chick he's 'in love with,' 'death, 'rebirth,' killing of mother, rebirth of mother, realisation that he is a 'monster,' loss of the 'good man,' identity, realisation that he's turned his mother into a monster, loss of the 'good son identity,' we're talking massive trauma here. William the victim turns into William the Bloody: the monster basically following whatever Angelus and Drusilla tell him to. He's in a 'kill or be killed,' world, and he's still being severley physically, emotionally, psycologically, etc. abused/played with by Angelus and Dru. All this trauma with 'a soul,' bringing awareness and emotion with it. Spike, eventually is what he becomes to survive. And just to back my theory up, here's a quote from Viktor Frankl, prisoner of Auschwitz, Holocaust Survivor:
“On average, only those prisoners could keep alive who…had lost all scruples in their fight for [b]existence[/b]; they were prepared to use every meants, honest and otherwise, even brutal force, theft, and betrayal of their friends, in order to save themselves. We who have come back…we know: the best of us did not return.”
To survive necessitates losing/severly harming/almost killing his soul. It's only when he's 'in jail,' no longer in the 'kill or be killed,' world, no longer bound to the person who killed him, that he's able to start ALLOWING to a GREATER degree the old William to come out more and more. And again Dawn (for me) is the key, not Buffy.
Which is really cool I think, because it means that all the evil, cruel, disgusting, etc. things that Spike has done are not because he didn't have a soul but were actually aspects of his identity, perhaps repressed that he allowed to surface. Kind of like if someone said, "you can do anything you want: you won't be punished, judged, held accountable, harmed, etc. in any way. In fact...you'll gain in status." That's quite the temptation for a human being, let alone one that's sharing his body with a demon. So Spike, eventually, would have to find out he's had a soul all along and then come to the realisation that it was him, William, all along, who did all the evil things he did. The REAL monster, lies not within the demon, but within the MAN! LOL
Hee Hee! Love to see either one of these! But heh! Can play them out in my mind or fanfics, yes? LOL